Showing papers by "Werner Hacke published in 1992"

Recombinant tissue plasminogen activator in acute thrombotic and embolic stroke

Abstract: An open angiography-based, dose rate escalation study on the effect of intravenous infusion of recombinant tissue plasminogen activator (rt-PA) on cerebral arterial recanalization in patients with acute focal cerebral ischemia was performed at 16 centers. Arterial occlusions consistent with acute ischemia in the carotid or vertebrobasilar territory in the absence of detectable intracerebral hemorrhage were prerequisites for treatment. After the 60-minute rt-PA infusion, arterial perfusion was assessed by repeat angiography and computed tomography scans were performed at 24 hours to assess hemorrhagic transformation. Of 139 patients with symptoms of focal ischemia, 80.6% (112) had complete occlusion of the primary vessel at a mean of 5.4 +/- 1.7 hours after symptom onset. No dose rate response of cerebral arterial recanalization was observed in 93 patients who completed the rt-PA infusion. Middle cerebral artery division (M2) and branch (M3) occlusions were more likely to undergo recanalization by 60 minutes than were internal carotid artery occlusions. Hemorrhagic infarction occurred in 20.2% and parenchymatous hematoma in 10.6% of patients over all dose rates, while neurological worsening accompanied hemorrhagic transformation (hemorrhagic infarction and parenchymatous hematoma) in 9.6% of patients. All findings were within prospective safety guidelines. No dose rate correlation with hemorrhagic infarction, parenchymatous hematoma, or both was seen. Hemorrhagic transformation occurred significantly more frequently in patients receiving treatment at least 6 hours after symptom onset. No relationship between hemorrhagic transformation and recanalization was observed. This study indicates that site of occlusion, time to recanalization, and time to treatment are important variables in acute stroke intervention with this agent.

Safety and efficacy of intravenous tissue plasminogen activator and heparin in acute middle cerebral artery stroke.

Abstract: There is little reported of the safety and efficacy of high-dose intravenous recombinant tissue plasminogen activator (alteplase) in combination with heparin anticoagulation in patients presenting with acute ischemic stroke.Thirty-two patients with severe hemispheric stroke syndrome caused by angiographically proven middle cerebral artery and/or intracranial internal carotid artery occlusion were treated with 100 mg alteplase by intravenous infusion over 90 minutes within a mean +/- SD of 226 +/- 68 minutes after symptom onset. Recanalization was assessed by digital subtraction angiography in all patients immediately after treatment and by transcranial Doppler monitoring (n = 30) and/or a third angiogram (n = 5) 12-24 hours later.Complete or partial reperfusion was observed in 11 patients (34%) 90 minutes after the initiation of alteplase infusion and in 17 patients (53%) within 12-24 hours. Hemorrhagic infarction without clinical deterioration was detected by follow-up computed tomography in nine patient...

Induction of FOS and JUN proteins after focal ischemia in the rat: differential effect of the N-methyl-D-aspartate receptor antagonist MK-801.

Abstract: FOS and JUN proteins are transcription factors thought to be involved in coupling neuronal excitation to target gene expression. Cortical infarction of consistent size and location was produced by irradiating the rat brain with Xenon light through the intact skull for 20 min following systemic injection of the photo-sensitizing dye, rose bengal. To investigate the time course and distribution pattern of five cellular ummediate early gene (IEG)-encoded proteins after focal ischemia, the expression of c-FOS, FOS B, c-JUN, JUN B and JUN D was studied immunocytochemically in sham-operated control animals and at different postischemic time intervals up to 24 h. A separate group of animals was pretreated with the non-competitive N-methyl-d-aspartate (NMDA) antagonist MK-801. Photochemically induced focal ischemia caused a rapid induction of FOS and JUN proteins in the entire ipsilateral cortex apart from the ischemic focus. Immunoreactivity in the ipsilateral subcortical gray and white matter and in the entire contralateral hemisphere was indistinguishable from control animals. Individual IEG-encoded proteins were sequentially induced with increased levels of immunoreactivity persisting for different time periods up to 24 h. c-FOS, FOS B, c-JUN and JUN B exhibited a characteristic distribution pattern as reflected by different staining intensities in individual cortical layers. The rapid IEG induction in the entire ipsilateral sensorimotor and limbic structure-associated cortices after photochemically induced infarction most likely reflects spreading depression caused by ischemia and mediated by NMDA receptors. This conclusion is supported by the finding that MK-801 pretreatment completely prevented the postischemic induction of FOS proteins and markedly attenuated the levels of JUN immunoreactivity in all cortical regions except in the peri-infarct area.

Pure motor hemiparesis with stable somatosensory evoked potential monitoring during aneurysm surgery: case report.

Abstract: We report a patient who sought treatment for an acute subarachnoid hemorrhage as a result of an intracranial aneurysm. Management included early surgical repair and intraoperative monitoring of evoked potentials. Pan-angiography revealed berry aneurysms of the communicating anterior artery and right middle cerebral artery. Surgery was uneventful, and the somatosensory evoked potential monitoring did not show any abnormalities. Nevertheless, the patient showed a neurological deficit due to a clip-related infarct in the right middle cerebral artery territory characterized by a right hemiparesis with no sensory deficit. This case report supports the possibility of false-negative results in single-mode intraoperative monitoring during aneurysm surgery.